With a rapid development of a display technique, a touch screen/panel has been popular in human's life. Currently, an In Cell touch panel has won favor with most of manufactures, because it can embed touch components into a display screen, reduce a thickness of an entire module and can also decrease a manufacture cost of the touch panel significantly. Therefore, a driving manner has also been a focus to be researched in the in cell touch panel.
A driving circuit in an existing optical touch panel comprises a plurality of stages of driving circuits for implementing a touch function. In particular, each stage of the driving circuit is as illustrated in FIG. 1 and comprises a photodiode PD, a capacitor Cst, a first transistor M1 and a second transistor M2; wherein a first terminal c1 of the capacitor Cst is connected with a constant voltage signal terminal RWS, a second terminal c2 of the capacitor Cst is connected with a first terminal p1 of the photodiode PD and a gate of the first transistor M1, respectively; a second terminal p2 of the photodiode PD is connected with a control signal terminal RST; a source of the first transistor M1 is connected with a high level signal terminal VDD, a drain of the first transistor M1 is connected with a source of the second transistor M2 and a read signal terminal Sensor, respectively; a gate of the second transistor M2 is connected with a reset signal terminal VB, and a drain of the second transistor M2 is connected with a low level signal terminal VSS.
In the driving circuit of the existing optical touch panel, if all of touch signal reading terminals of the respective stages of the driving circuits are connected to a same touch signal reading line collectively, a crosstalk can occur in signals outputted from the touch signal reading terminals of the different stages of the driving circuits, and in turn an accuracy of a detection of the touch signals on the touch panel will be affected. If the touch signal reading terminals of the respective stages of the driving circuits are provided with touch signal reading lines, respectively, a wiring area of the touch panel would increase undesirably.